Linux

For a while now I've been evaluating some 32-bit micro controllers for a future product. One of them was the STM32L15x series. There are some handy development boards available such as the Nucleo boards. Since we need to have the ability to program processors from Linux for our small production line, tool support is one of the checkboxes that need to be ticked.

For the STM32 series, flashing the microcontroller can be done through GDB, OpenOCD, and the STLink tool. One issue that arose however was the need to program the EEPROM available on the STM32L series. This requirement comes from need to generate and program different EEPROM content on a per board basis at the production line. Doing that requires a few tweaks that are documented below...

Some time ago I followed an interesting discussion on a board where people were discussing multi-core software development. During the course of the discussion it became apparent that there is a lot of confusion and misconceptions about a 'process' and a 'thread' as they exist on e.g., a Linux system. Both are applicable to make use of multi-core systems, but they do so in different ways. Even though the exact distinction while compared to early definitions of the terms has perhaps become somewhat blurred, the two remain separate entities which can complement each other perfectly. In this post I'm going to try and illustrate the similarities and differences, and show you some real life scenarios of both. Keep in mind that we will be making some generalizations - and there are lots of examples where these generalizations do not directly apply, or where there are other possible implementations of the cited examples. Going into these would turn this blog entry into an entire book...

Some time ago we had a project which needed a simple transparent caching proxy for use in classrooms in Latin America. The classroom desktops consisted of ten of our Efika's, and we thought why not use an extra one of those to act as the proxy. This is not the kind of high bandwidth environment of a typical installation, so the performance limitations were not really an obstacle. The goal was rather to use the limited internet connection available as efficiently as possible. The configuration of the system using Squid is detailed below.